Multi-layer bandwidth recovery for multimedia communications: an experimental evaluation

Multimedia communications, such as real-time video and audio streaming, have stringent quality of service requirements (e.g., throughput and delay) that must be seamlessly guaranteed in spite of network state changes. Thus if connections carrying multimedia traffic become unreliable (i.e., they do not satisfy any more their QoS constraints) they must be recovered to regain their pre-failure QoS guarantees (e.g., minimum bandwidth). In this study schemes that recover a bandwidth guaranteed client-server connection, i.e. bandwidth recovery schemes, from physical network failures, link congestion, and connection pre-emption are implemented both at the multi-protocol label switching (MPLS) layer and at the application and evaluated. Experimental results show that, thanks to the different failure detection methods utilized by each scheme, the implemented schemes form a coordinated multi-layer bandwidth recovery scheme. The implemented MPLS layer and application layer bandwidth recovery schemes allow to overcome all the considered failure scenarios.